Nutrition and energy status

Diet composition is often regarded to constitute a species specific trait with certain food types being dominant over others. In the context of human evolution, the change from a plant based diet (herbivory) to a mixed diet combining several types of food (omnivory) is regarded a prime mover paving the way for other developments such as cooperation, food sharing, and technologies of food processing. Evolutionary models associate the emergence of these traits with relatively dry habitats, pronounced seasonality, and shortage of fruit bearing trees which implies that these traits would not have evolved in high productivity forest habitats. Some traits of bonobo feeding behaviour, namely the absence of tool use, the relatively low investment in food processing, and the lower frequency of meat eating seem to support such models. This work is combined this with data on the nutritional status and energy supply, using stable isotopes and other nutritional markers that can be extracted from non-invasive samples such as urine and faeces. In conjunction with this work experimental studies are conducted to explore the efficiency of digestion of certain macronutrients such as fat, starch, and structural carbohydrates to evaluate the capacity of bonobos and other Great apes to utilize macronutrients under changing environmental conditions.